1. Field of the Invention
The present invention relates to a software download system in which a computer software product such as a computer program is downloaded with a broadcasting program from a center station to each terminal through a communication satellite, a broadcasting satellite or a terrestrial television broadcasting service in a digital broadcasting.
2. Description of the Related Art
A broadcasting system, in which a video signal and an audio signal composing a broadcasting program are digitized and the digital signals of the broadcasting program are transmitted from a transmitting station to a receiving apparatus through a broadcasting satellite, has been spread. Because digital data is transmitted through a satellite or a terrestrial television broadcasting service, it becomes possible that a digitized computer program is transmitted through a satellite or a terrestrial television broadcasting service in addition to the digital video signal and the digital audio signal and is stored in a storing unit of the receiving apparatus.
2.1. Previously Proposed Art
A broadcasting method, in which a computer program (or a computer software product) transmitted through a satellite is received in a receiving apparatus and is stored in a storing unit of the receiving apparatus, is disclosed in a Published Unexamined Japanese Patent Application No. H8-195952 (1996). The broadcasting method is described with reference to FIG. 1.
As shown in FIG. 1, in a digital data receiving and processing apparatus 2000 of a user, an electric wave indicating a broadcasting signal is transmitted through a satellite and is received in an antenna 2001, the electric wave received in the antenna 2001 is converted into the broadcasting signal in a converter 2002 by changing a frequency of the electric wave, the demodulation and error correction are performed for the broadcasting signal in a front end 2003 to obtain a digital signal, and the digital signal is transmitted to a transport block 2004. In the transport block 2004, the digital signal is divided into video data, audio data and conditional access data including a computer program. Because the broadcasting signal is enciphered, the conditional access data is transmitted to an IC card 2006 through an IC card interface 2005, and the judgement whether or not the user has an access right for the broadcasting signal is performed according to the conditional data by the IC card 2006. In cases where the user has an access right for the broadcasting signal, a cryptograph key used for the cryptanalysis is delivered from the IC card 2006 to the transport block 2004, and the video data, the audio data and the conditional access data are deciphered in the transport block 2004 by using the cryptograph key. The video data deciphered is decoded in a video decoder 2007 to produce decoded video data, the decoded video data is encoded in an NTSC encoder 2008 to produce an National Television System Committee (NTSC) type video signal, and the NTSC type video signal is output. The audio data deciphered is decoded in an audio decoder 2009 to produce audio signal, and the audio signal is output. Also, the computer program included in the deciphered conditional access data is stored in an electrically erasable and programmable read only memory (EEPROM) 2100 under control of a central processing unit (CPU) 2101. The processing of the CPU 2101 is performed according to a processing program stored in a ROM 2102, and data necessary for the processing of the CPU 2101 is stored in a RAM 2103.
2.2. Problems to be Solved by the Invention
However, because the computer program is included in the conditional access data and because the computer program included in the conditional access data is always broadcasted with the video and audio data, a special frequency band used only for the computer program is required. Therefore, there is a problem that a frequency band required for the transmission of the broadcasting signal is widened.
Also, because any computer program (or any computer software product) for presenting a broadcasting program guide including a broadcasting schedule and downloading one broadcasting program is not transmitted to the digital data receiving and processing apparatus 2000, the user cannot select a desired broadcasting program from a plurality of broadcasting programs by watching a plurality of broadcasting program guides displayed on an image screen.
An object of the present invention is to provide, with due consideration to the drawbacks of such a conventional broadcasting method, a software download system in which a software product such as a computer software product is downloaded to user""s terminal without requiring a special frequency band used only for the software product.
The object of the present invention is achieved by the provision of a software download system, comprising:
broadcasting program guide preparing means of a center station for preparing a guide of a broadcasting program accompanied by a software product corresponding to a first version number, a version number of the software product being changed each time the software product is revised in the center station;
broadcasting program data storing means of the center station for storing data of the broadcasting program which is listed in the guide prepared by the broadcasting program guide preparing means;
software storing means of the center station for storing data of the software product which is listed in the guide prepared by the broadcasting program guide preparing means;
transmitting means of the center station for transmitting the guide of the broadcasting program with the software product prepared by the broadcasting program guide preparing means, and transmitting the data of the software product stored in the software storing means with the data of the broadcasting program stored in the broadcasting program data storing means during a transmission time period of the broadcasting program through the same transmission channel as that of the broadcasting program under the control of the broadcasting program guide preparing means;
receiving means of a terminal for receiving the guide of the broadcasting program with the software product from the transmitting means, and receiving the data of the software product with the data of the broadcasting program during the transmission time period from the transmitting means;
output means of the terminal for outputting the data of the broadcasting program received by the receiving means during the transmission time period;
version number managing means of the terminal for managing a second version number corresponding to the software product previously downloaded from the center station to the terminal;
download judging means of the terminal for checking whether or not the first version number of the software product of the guide received by the receiving means differs from the second version number of the software product managed by the version number managing means and judging to download the data of the software product received by the receiving means to the terminal in cases where the first version number of the software product listed in the guide differs from the second version number of the software product managed by the version number managing means; and
downloading means of the terminal for extracting the data of the software product from the broadcasting program received by the receiving means during the transmission time period in cases where the downloading of the software product is judged by the download judging means and storing the data of the software product to download the software product received by the receiving means from the center station to the terminal and to use the software product on user""s side.
In the above configuration, a guide of a broadcasting program is prepared in the broadcasting program guide preparing means. In the guide, a software product to be transmitted with the broadcasting program is listed, a first version number indicating the version of the software product is listed, and a transmission time period of the broadcasting program is listed. The guide is transmitted from the transmitting means to the receiving means.
Also, data of the software product stored in the software storing means is transmitted from the transmitting means to the receiving means with data of the broadcasting program stored in the broadcasting program data storing means during the transmission time period through the same transmission channel as that of the broadcasting program under the control of the broadcasting program guide preparing means.
In the terminal, a second version number indicating the version of the software product previously downloaded is managed in advance by the version managing means. When the guide is received by the receiving means, it is checked by the download judging means whether or not the first version number of the software product of the guide differs from the second version number of the software product managed by the version managing means. In cases where the first version number of the software product of the guide differs from the second version number of the software product, because the software product is renewed in the center station, it is judged to download the software product received by the receiving means to the terminal. Therefore, in the downloading means, the data of the software product is extracted from the broadcasting program received by the receiving means during the transmission time period, so that the software product is downloaded from the center station to the terminal and is stored. Therefore, the user can use the software product. For example, in cases where a computer software product representing the software product is downloaded to user""s terminal, the user can execute the computer software product in user""s computer.
Accordingly, because data of the software product is transmitted from the center station to the terminal with data of the broadcasting program, the software product can be downloaded to user""s terminal without requiring a special frequency band (or a special transmission channel) used only for the software product.
Also, in cases where the software product is revised in the center station, because the first version number of the software product of the guide differs from the second version number of the software product already managed by the version managing means, the revision of the software product can be detected by the download judging means, so that the software product can be downloaded from the center station to the terminal. Therefore, the user can always use the updated software product.
It is preferred that the software download system further comprise:
set-up information storing means of the center station for storing set-up information indicating a download completion notification flag, the set-up information being included in the guide prepared by the broadcasting program guide preparing means;
download completion notification judging means of the terminal for judging whether or not the downloading of the software product performed by the downloading means is to be notified to the center station, the notification of the downloading of the software product being judged by the download completion notification judging means according to the download completion notification flag;
download completion notice transmitting means of the terminal for transmitting an identification number of the terminal and a name of the software product downloaded by the downloading means as a download completion notice to the center station in cases where the download completion notification judging means judges that the downloading of the software product performed by the downloading means is to be notified; and
download record managing means of the center station for managing a record of the downloading of the software product performed in the terminal according to the identification number of the terminal and the name of the software product transmitted from the download completion notice transmitting means.
In this configuration corresponding to a second embodiment, in cases where a software product supplier wants to know that the software product transmitted with the broadcasting program is downloaded from the center station to the user""s terminal, because a download completion notice flag corresponding to the software product is set in the set-up information, the request of a download completion notice can be recognized in the terminal by checking the download completion notice flag of the software product written in the guide of the broadcasting program.
Accordingly, in cases where the software product is actually downloaded from the center station to the terminal, the software product supplier can know the downloading of the software product by checking the identification number of the terminal.
It is also preferred that the software download system further comprise:
protocol processing means of the center station for processing the data of the software product stored in the software storing means according to each of a plurality of software communication protocols to produce a plurality of protocol-processed software products, each protocol-processed software product being communicable with a type of terminal according to one software communication protocol, the protocol-processed software products being transmitted from the transmitting means to the receiving means of the terminal, and a particular protocol-processed software product selected from the protocol-processed software products being received by the terminal on condition that a type of the terminal matches with a particular software communication protocol corresponding to the particular protocol-processed software product.
In this configuration corresponding to a seventh embodiment, even though a plurality of terminals are classified into a plurality of groups respectively corresponding to one software communication protocol, because a plurality of protocol-processed software products corresponding to a plurality of software communication protocol types are prepared from each software product and are transmitted to the terminals, one type protocol-processed software product can be reliably received in each terminal.
It is also preferred that the software download system further comprise:
protocol processing means of the center station for processing the data of the software product stored in the software storing means according to a particular software communication protocol to produce a particular protocol-processed software product communicable according to the particular software communication protocol, a name of the particular software communication protocol being listed in the guide of the broadcasting program prepared by the broadcasting program guide preparing means, the particular protocol-processed software product being transmitted from the transmitting means to the receiving means of the terminal, and the particular protocol-processed software product being received by the receiving means;
protocol processing program storing means of the terminal for storing one or more protocol processing programs respectively used for a protocol processing in which one protocol-processed software product communicable according to one software communication protocol is changed to data of one software product;
protocol correspondence table holding means of the terminal for holding a protocol correspondence table in which the correspondence of one software communication protocol and one protocol processing program is listed for each protocol processing program stored in the protocol processing program storing means;
software communication protocol judging means of the terminal for checking whether or not the particular software communication protocol, of which the name is listed in the guide of the broadcasting program received by the receiving means, is listed in the protocol correspondence table held by the protocol correspondence table holding means in cases where the download judging means judges to download the software product, and outputting the name of the particular software communication protocol in cases where the particular software communication protocol is listed in the protocol correspondence table; and
protocol processing performing means of the terminal for receiving the name of the particular software communication protocol output from the software communication protocol judging means, extracting a particular protocol processing program corresponding to the particular software communication protocol from the protocol processing program storing means, performing a protocol processing for the particular protocol-processed software product received by the receiving means according to the particular protocol processing program to change the particular protocol-processed software product to the software product, the software product being downloaded by the downloading means.
In this configuration corresponding to an eighth embodiment, even though a particular protocol-processed software product communicable according to a particular software communication protocol is transmitted with one broadcasting program from the center station to the terminal, in cases where a particular protocol processing program for changing the particular protocol-processed software product to a software product is arranged in the terminal, the particular protocol-processed software product can be changed to the software product by executing the particular protocol processing program, and the software product can be downloaded to the terminal.
The object of the present invention is also achieved by the provision of a software download system, comprising:
broadcasting program guide preparing means of a center station for preparing guides of a first group of broadcasting programs and guides of a second group of broadcasting programs, each broadcasting program of the first group being accompanied by a software product corresponding to a first version number, each broadcasting program being not accompanied by any software product, and a version number of the software product being changed each time the software product is revised in the center station;
broadcasting program data storing means of the center station for storing data of each broadcasting program of which the guide is prepared by the broadcasting program guide preparing means;
software storing means of the center station for storing data of one software product corresponding to the first version number for each software product of which the guide is prepared by the broadcasting program guide preparing means;
transmitting means of the center station for transmitting the guides of the broadcasting programs prepared by the broadcasting program guide preparing means, transmitting the data of each broadcasting program stored in the broadcasting program data storing means during a transmission time period of the broadcasting program under the control of the broadcasting program guide preparing means, and transmitting the data of each software product stored in the software storing means with the data of one broadcasting program through the same transmission channel as that of the broadcasting program under the control of the broadcasting program guide preparing means;
receiving means of a terminal for receiving the guides of the broadcasting programs from the transmitting means, and receiving the data of the broadcasting programs and the data of the software products from the transmitting means;
output means of the terminal for outputting the data of each broadcasting program received by the receiving means during the transmission time period;
version number managing means of the terminal for managing a second version number corresponding to each software product previously downloaded from the center station to the terminal;
broadcasting software program extracting means of the terminal for extracting the guide of each broadcasting program of the first group from the guides received by the receiving means as a guide of one broadcasting software program;
download judging means of the terminal for checking whether or not the first version number of the software product of the broadcasting software program of each guide extracted by the broadcasting software program extracting means differs from the second version number of the software product managed by the version number managing means and judging to download the software product of each broadcasting software program received by the receiving means to the terminal in cases where the first version number of the software product differs from the second version number of the software product; and
downloading means of the terminal for extracting the data of the software product from the broadcasting program received by the receiving means during the transmission time period in cases where the downloading of the software product is judged by the download judging means and storing the data of the software product to download the software product received by the receiving means from the center station to the terminal and to use the software product on user""s side.
In the above configuration, guides of a plurality of broadcasting programs are prepared in the broadcasting program guide preparing means. The guides are transmitted from the transmitting means to the receiving means.
Also, data of each broadcasting program stored in the broadcasting program data storing means is transmitted from the transmitting means to the receiving means during its transmission time period, and data of each software product stored in the software storing means is transmitted with one broadcasting program from the transmitting means to the receiving means during the transmission time period of the broadcasting program through the same transmission channel as that of the broadcasting program under the control of the broadcasting program guide preparing means.
In the terminal, a second version number indicating the version of the software product previously downloaded is managed in advance by the version managing means. When the guides are received by the receiving means, the guide of each broadcasting program with one software product is extracted from all guides by the broadcasting software program extracting means as a guide of one broadcasting software program, and it is checked by the download judging means whether or not the first version number of one software product transmitted with each broadcasting software program differs from the second version number of the software product managed by the version managing means. In cases where the first version number of the software product differs from the second version number of the software product, because the software product is renewed in the center station, it is judged to download the software product received by the receiving means to the terminal. Therefore, in the downloading means, the data of the software product is extracted from the broadcasting program received by the receiving means during the transmission time period, so that the software product is downloaded from the center station to the terminal and is stored. Therefore, the user can use the software product. For example, in cases where a computer software product representing the software product is downloaded to user""s terminal, the user can execute the computer software product in user""s computer.
Accordingly, because data of each software product is transmitted from the center station to the terminal with data of the broadcasting program through the same transmission channel as that of the broadcasting program, the software product can be downloaded to user""s terminal without requiring a special frequency band (or a special transmission channel) used only for the software product.
Also, in cases where one software product is revised in the center station, because the first version number of the software product of the guide differs from the second version number of the software product already managed by the version managing means, the revision of the software product can be detected by the download judging means, so that the software product can be downloaded from the center station to the terminal. Therefore, the user can always use the updated software product.
It is preferred that the software download system further comprise:
set-up information storing means of the center station for storing set-up information indicating a software type of one software product for each software product of the guides prepared by the broadcasting program guide preparing means, each software product being set to a first software type or a second software type, and the pieces of set-up information of the software products being added to the guides by the broadcasting program guide preparing means;
display broadcasting program extracting means of the terminal for extracting one or more guides of display broadcasting programs with software products set to the first software type from the guides of the broadcasting programs received by the receiving means;
display broadcasting program displaying means of the terminal for displaying the guides of the display broadcasting programs extracted by the display broadcasting program extracting means for a user to select one or more download-candidate display broadcasting programs from the display broadcasting programs, all guides of broadcasting programs with software products set to the second software type being extracted from the guides of the broadcasting programs received by the receiving means as one or more guides of broadcasting software programs by the broadcasting software program extracting means, the guides of the broadcasting software programs being added to the guides of the download-candidate display broadcasting programs, the downloading of the software product transmitted with each download-candidate broadcasting program being judged by the download judging means in cases where the first version number of the software product differs from the second version number of the software product, and the downloading of the software product transmitted with each download-candidate broadcasting program being performed by the downloading means.
In this configuration corresponding to a third embodiment, a software product supplier of the center station sets one software product to a first type in cases where the software product supplier desires a user to judge whether or not the downloading of the software product from the center station to user""s terminal is to be performed. Accordingly, a guide of a broadcasting program with the software product can be displayed, and the user can judges the downloading of the software product.
It is also preferred that the software download system further comprise:
software download reservation managing means of the terminal for managing the recording reservation for one or more recording-reserved broadcasting programs selected from the second group of broadcasting programs, of which the guides are prepared by the broadcasting program guide preparing means; and
download-reserved broadcasting program determining means of the terminal for selecting a guide of a download-reserved broadcasting program from guides of one or more broadcasting programs, of which the software products are judged by the download judging means to be downloaded to the terminal, on condition that a transmission time period of the download-reserved broadcasting program does not overlap with that of any recording-reserved broadcasting program managed by the software download reservation managing means, the software product transmitted with the download-reserved broadcasting program being downloaded by the downloading means.
In this configuration corresponding to a fourth embodiment, even though the recording of one or more broadcasting programs respectively accompanied by no software product is reserved, one or more download-reserved broadcasting programs can be selected from the broadcasting programs on condition that a transmission time period of each download-reserved broadcasting program does not overlap with that of any broadcasting program, and the download-reserved broadcasting programs can be downloaded to record the software product of each download-reserved broadcasting program during its transmission time period.
It is also preferred that the software download system further comprise:
software product displaying and selecting means of the terminal for displaying names of the software products of the broadcasting software programs, which are listed in the guides extracted by the broadcasting software program extracting means, and receiving names of one or more particular software products selected from the software products, the downloading of each particular software product being judged by the download judging means, and the particular software product being downloaded by the downloading means in cases where the download judging means judges to download the particular software product.
In this configuration corresponding to a fifth embodiment, names of software products transmitted with the broadcasting software programs are displayed. Accordingly, the user can select one or more particular software products in cases where the user desires to download the particular software products from the center station.
Also, because only the software name is displayed, the user can select each particular software product without considering the transmission time period.
It is also preferred that the software download system further comprise:
software download reservation managing means of the terminal for managing the recording reservation for one or more first recording-reserved broadcasting programs selected from the second group of broadcasting programs, of which the guides are prepared by the broadcasting program guide preparing means, and newly managing the recording reservation for a second recording-reserved broadcasting program selected from the second group of broadcasting programs, of which the guides are prepared by the broadcasting program guide preparing means;
download-reserved broadcasting program determining means of the terminal for selecting a guide of a first particular download-reserved broadcasting program from guides of one or more particular broadcasting programs, which include the same particular software product judged by the download judging means to be downloaded to the terminal, on condition that a transmission time period of the first download-reserved broadcasting program does not overlap with any of the first recording-reserved broadcasting program managed by the software download reservation managing means; and
duplication reservation detecting means of the terminal for detecting that a transmission time period of the first particular download-reserved broadcasting program overlaps with that of the second recording-desired broadcasting program newly managed by the software download reservation managing means, transmitting information indicating the duplication reservation of the first particular download-reserved broadcasting program to the download-reserved broadcasting program determining means to select a guide of a second particular download-reserved broadcasting program relating to a specific transmission time period from the guides of the particular broadcasting programs in the download-reserved broadcasting program determining means on condition that the specific transmission time period of the second particular download-reserved broadcasting program does not overlap with that of any first recording-desired broadcasting program or the second recording-desired broadcasting program, and transmitting the guide of the second particular download-reserved broadcasting program relating to the specific transmission time period to the software download reservation managing means, the particular software product transmitted with the second particular download-reserved broadcasting program being downloaded by the downloading means at the specific transmission time period under the control of the software download reservation managing means.
In this configuration corresponding to a sixth embodiment, even though the user reserves the recording of a second recording-desired broadcasting program of which a transmission time period overlaps with a transmission time period of a first particular download-reserved broadcasting program registered in a reservation table, the first particular download-reserved broadcasting program relating to the transmission time period is removed, and a second particular download-reserved broadcasting program relating to a specific transmission time period is selected on condition that the specific transmission time period of the second particular download-reserved broadcasting program does not overlap with that of any recording-desired broadcasting program. Accordingly, the recording of the second recording-desired broadcasting program and the downloading of the second particular download-reserved broadcasting program can be performed.
It is also preferred that the data of each broadcasting program is transmitted by the transmitting means at a transmission channel, the data of each software product transmitted with one broadcasting program is transmitted by the transmitting means at the same transmission channel as that of the broadcasting program, the data of a group of broadcasting programs corresponding to a plurality of transmission channels and the data of one or more software products respectively transmitted with one broadcasting program of the group are transmitted as a transport stream, a plurality of transport streams are transmitted from the transmitting means to the receiving means, one of the transport streams is received by the receiving means, one transmission channel and a transport stream identifier are listed in the guide of each broadcasting program by the broadcasting program guide preparing means, and the software download system further comprise:
audience rating managing means of the center station for managing a broadcasting program audience rating table in which an audience rating of each broadcasting program, of which the guide is prepared by the broadcasting program guide preparing means, is listed, a broadcasting program of a high audience rating being set as a specific broadcasting program transmitted at a first transmission channel by the broadcasting program guide preparing means, and a transmission channel of a particular broadcasting program with a particular software product being set to a second transmission channel differing from the first transmission channel by the broadcasting program guide preparing means to transmit the particular broadcasting program with the specific broadcasting program as a specific transport stream;
channel setting means of the terminal for setting a transmission channel of one broadcasting program, of which the data is output to the output means, to the first transmission channel of the specific broadcasting program, the specific transport stream, in which the data of the specific broadcasting program transmitted at the first transmission channel is included, being specified by the receiving means; and
transmission channel checking means of the terminal for receiving a specific transport stream identifier of the specific transport stream listed in a guide of the specific broadcasting program, of which the data is transmitted at the first transmission channel and is received by the receiving means to be output to the output means, from the receiving means, checking whether or not a particular transport stream identifier listed in the guide of the particular broadcasting program with the particular software product, which is transmitted at the second transmission channel and at the same transmission start time as that of the specific broadcasting program and is judged by the download judging means to be downloaded, agrees with the specific transport stream identifier of the specific transport stream, and transmitting a download-performable notice and the guide of the particular broadcasting program to the downloading means in cases where the particular transport stream identifier agrees with the specific transport stream identifier, the particular software product being downloaded by the downloading means according to the download-performable notice and the guide of the particular broadcasting program.
In this configuration corresponding to a ninth embodiment, the broadcasting of a particular broadcasting program with a particular software product is set to the same transmission time period as that of a specific broadcasting program not accompanied by any software product in the center station on condition that the transmission channel of the particular broadcasting program and the transmission channel of the specific broadcasting program differ from each other and are included in the same transport stream to simultaneously receive the particular broadcasting program and the specific broadcasting program in the terminal.
Accordingly, even though a user does not select the particular broadcasting program but select the specific broadcasting program, the particular software product transmitted with the particular broadcasting program can be downloaded to the terminal.
Also, because a broadcasting program expected to be watched by users at high audience rating is set as the specific broadcasting program, the specific broadcasting program is expected to be watched by users at high probability, so that the particular software product transmitted with the particular broadcasting program can be downloaded to the terminal at high probability.
It is also preferred that the software download system further comprise:
software product displaying and selecting means of the terminal for displaying names of the software products of the broadcasting software programs, which are listed in the guides extracted by the broadcasting software program extracting means, receiving a name of a particular software product selected from the software products and receiving a former-version selecting instruction, the name of the particular software product selected and the former-version selecting instruction being received by the download judging means; and
software product renewal managing means for managing a software product renewal table in which a renewed version number of one software product currently downloaded by the downloading means and a former version number of the software product previously downloaded by the downloading means before the renewal to the software product of the renewed version number are listed for each software product of which the guide is prepared by the broadcasting program guide preparing means, the former version number of the particular software product being recognized by the download judging means according to the former-version number selecting instruction, a guide of the particular software product of the former version number being transmitted from the broadcasting software program extracting means to the download judging means, the downloading of the particular software product of the former version number being judged by the download judging means, and the particular software product of the former version number being downloaded by the downloading means.
In this configuration corresponding to a tenth embodiment, even though the user is not satisfied with an updated software product obtained by renewing a software product of the former version number, because the software product of the former version number is transmitted with one broadcasting program, the user can download the software product of the former version number to replace the updated software product with the software product of the former version number. Therefore, the user can again use the software product of the former version number. For example, in cases where a computer software product representing the software product is downloaded to user""s terminal, the user can again execute the computer software product of the former version number in user""s computer to perform a computer operation.
The object of the present invention is also achieved by the provision of a software download system, comprising:
broadcasting program guide preparing means of a center station for preparing a guide table in which guides of one or more broadcasting programs and a guide of a software product corresponding to a first version number are listed, a version number of the software product being changed each time the software product is revised in the center station;
broadcasting program data storing means of the center station for storing data of each broadcasting program which is listed in the guide table prepared by the broadcasting program guide preparing means;
software storing means of the center station for storing data of the software product of which the guide is listed in the guide table prepared by the broadcasting program guide preparing means;
transmitting means of the center station for transmitting the guide table prepared by the broadcasting program guide preparing means, transmitting the data of each broadcasting program stored in the broadcasting program data storing means during a transmission time period of the broadcasting program under the control of the broadcasting program guide preparing means and transmitting the data of the software product stored in the software storing means through the same transmission channel as that of one broadcasting program during a specific time period in which any broadcasting program is not transmitted through the transmission channel;
receiving means of a terminal for receiving the guide table from the transmitting means, receiving the data of each broadcasting program from the transmitting means during the transmission time period and receiving the data of the software product from the transmitting means during the specific time period;
output means of the terminal for outputting the data of each broadcasting program received by the receiving means during the transmission time period;
version number managing means of the terminal for managing a second version number corresponding to the software product previously downloaded from the center station to the terminal;
download judging means of the terminal for checking whether or not the first version number of the software product of the guide received by the receiving means differs from the second version number of the software product managed by the version number managing means and judging to download the data of the software product received by the receiving means to the terminal in cases where the first version number of the software product listed in the guide differs from the second version number of the software product managed by the version number managing means; and
downloading means of the terminal for downloading the data of the software product received by the receiving means to the terminal during the specific time period in cases where the downloading of the software product is judged by the download judging means, the software product being used on user""s side.
In the above configuration, a guide of a software product corresponding to a first version number are listed in the guide table prepared by the broadcasting program guide preparing means, and the data of the software product is transmitted from the center to the terminal through a transmission channel (or a frequency band) during a specific time period in which any broadcasting program is not transmitted through the transmission channel.
Accordingly, the software product can be downloaded from the center to the terminal without any private frequency band.
Also, in cases where the software product is revised in the center station, because the first version number of the software product of the guide differs from the second version number of the software product already managed by the version managing means, the revision of the software product can be detected by the download judging means, so that the software product can be downloaded from the center station to the terminal. Therefore, the user can always use the updated software product.